1. Field of the Invention
The present invention relates to a method of manufacturing a luminous sheet radiating fluorescence upon irradiation of ultraviolet rays, and more particularly to a method of manufacturing a luminous sheet which has a double-layered structure comprised of a light emitting layer containing a fluorescent material therein and a back layer, the back layer of the luminous sheet being fixed to a certain location where ultraviolet rays are irradiated to the light emitting layer on the front side, thereby easily providing a planar fluorescent display unit.
2. Description of the Related Art
Heretofore, it has been customary to draw pictures, characters or the like by using a mixture of a fluorescent material and an appropriate binder, and irradiating ultraviolet rays to the mixture so that fluorescence is radiated to present a variety of display.
Such a conventional method is usually practiced by preparing an ultraviolet-excited luminous material in which a powder pigment of fluorescent material is dispersed in screen ink made of primarily a colorless, transparent acrylic resin or ink made of primarily a colorless, transparent epoxy resin in a ratio of 2:1 by weight, coating the material on a signboard or the like by screen printing, spray printing or brush painting, and then drying the coated material for about 15 minutes at 60.degree. C. to make the material fixed in place.
In other words, the conventional method has had disadvantages of requiring a plate for screen printing, entailing a drying time, and needing a skill for spray printing or brush painting.